Speed-varying mechanism.



No. 813,651. 1 PATENTED PEB. 27, 1906. J. B. LADD. SPEED VARYINGMEGHANISM.

APPLICATION FILED AUG. 8, 1904.

5 SHEETS-SHEET 1.

IHHIHIHIIIIIH TTOHNEY.

PATENTBD 11213.27, 1906.

5 SHEETS-SHEET 2.

Wl T//ESSES PATENTBD FEB. 27, 1906.

J. B. LADD. SPEED VARYING MEGHANISM.

APPLICATION FILED AUG. 8, 1904.

5 SHEETS-SHEET 3.

NVENTH WI Tl/ESSES PATENTED PEB. 27, 1906.

J. B. LADD. SPEED VARYING MECHANISM.

APPLICATION FILED AUG. 8. 1904.

5 SHEETS-SHEET 4.

Wmvessfs.A 7%@ .517% 44 No. 813,651. PATENTED FEB. 27, 1906.

J. B. LADD.

SPEED VARYING MEGHANISM. APPLIGATION FILED AUG. a, 1904.

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vSPEED-ft/AFIYING IVIECHANISNI.

Specification of Letters Patent.

Patented Feb. 2'7, 1906.

Application filed August 8, 1904. Serial No. 219,824.

. specification.

My invention relates to improvements in speed-varying mechanism, myobject being to provide mechanismwhereby variations in speed areobtained from driving mechanism of constant speed.

My invention comprises, essentially, an expansible wheel.

My specific device herein illustrated and described provides means forvarying the relative diameters of a pair of belt-connected pulleyswithout stopping the operation of the same.

My invention also comprises improved means for maintaining a continuousunbroken periphery or belt-carrying surface throughout the range of saidvariation in said pulley diameter.

My invention also comprises. automatic means for limiting the operationof the varying means.

My invention also comprises means for maintaining the normal or requiredtension of the belt between said pairI of pulleys unimpaired by therelative contraction and eX- pansion thereof.

Among the advantages of my improvements are that my mechanism is adaptedfor use in connection with ordinary or standard belts, that saidmechanism is compact, simple, and positive in operation, and as there isno lateral thrust in connection with the operation of my mechanism lossof power is saved in this respect and the necessity of complicatedball-bearing collars is obviated.

1n the accompanying drawings, Figure 1 is a plan view of the mechanismcontaining my improvements. Fig. 2 is.a side elevation of same. Fig. 3is an end elevation of same. Fig. 4 is a view of the face of the pulleyprovided with radial slots or guide-channels, one-half of said pulleyshowing the position of the parts when the same is fully expanded,while. the other half shows their position when the same is contracted.Fig. 5 shows the scrollplate that fits upon the opposite side of theface of the pulley shown in Fig. 4.

- 7 of Fig. 8.

Fig. 6 is a partial view in cross-section on line 6 6 of Fig. 4. Fig. 7is a section on line 7 Fig. 7a is a section on line 7L 7'Ll of Fig. 4.Fig. 8 is an inside view of side plate 23 with the mechanism attachedthereto. Fig. 9 is a section on line 9 9 of Fig. 8. Fig. 1() is aninside view of scroll-plate 4. Fig. 11 is a fragmentary view, enlarged,showing two adjustments of the pulley. Fig. 12 is a fragmentary view,enlarged, of the middle portions, as shown in Fig. 7.

Similar numerals refer to similar parts throughout the several views.

Referring to Figs. 1, 2, and 3, it will be seen that my devicecomprises-the pulleys 1 and 2, 1 being driven by the belt 3 from thesource of power, 2 being connected by belt 4 with the machine or otherdevice to be operated and for which a variation in speed is desired.Pulleys 1 and 2 are operatively connected by the pulleys 5 and 6 andbelt 7. By variation in the relative diameters of pulleys 5 and 6 itwill be obvious that a variation in the speed of pulley 2 will result,the speed of pulley 1 being presumed to be constant. The means foraccomplishing this relative variation in the diameters of pulleys 5 and6 without stopping or interfering with the operation or rotation of theparts and without im airing the normal or proper tension of the helft 7are among the objects of my invention. I accomplish this by mechanismarbitrarily operated by the shaft 8, controlled by handlever 9. Thismechanism controls in a similar way each pulley 5 and 6 and may bedescribed as follows: Referring to Fig. 4, the pulley is provided withthe side plate 10, having a series of radial slots or guide-channels 11.1n slots or guide-channels 11 are secured the members 12, which areadapted to slide radially in said slots or guide-channels. These members12 are provided with the overlapping plates 13 and constituteface-forming sections which coperate in forming a continuous unbrokenperiphery or face for the belt. These overlapping plates or members 13are best shown in Figs. 4 and 11. They consist of long spring-platesveach secured at one end in a recess in a member 12, respectively, thefree end extending over an adjoining member 12 and the plate 13 securedthereto. f Vhen the pulley is in the most contracted position, eachplate 13 will overlap a number of plates 13, as shown in the lower partof Fig. 11, and when the pulley is in the expanded position each plate13 will overlap a portion of the adjoining plate 13 and its member 12,as shown inthe upper part of Fig. 1.1. Thus it will be seen that thepulley has a capacity of expansion from a minimum diameter to threetimes 'said diameter without breaking the continu.

o'us peripheral surface of the pulley. It is also to be noted that thespring-plates 13 are given such a spring set as will cause them tocontract tightly one upon the other even when the pulley is mostcontracted, so that the free end of each plate 13 is held tightly uponthe underlying plate to maintain a smooth surface therebetween. Thespring tension of these plates in the direction above described is alsosuch as to resist any tendency to outward movement away from the axis ofthe pulley due to the centrifugal force exerted by the pulleys rotation.Beyond these plates 13 are secured the flanged extensions 14, integralwith members 12 as supports or braces therefor. Upon the extensions 15of members 12, which project through the slots or guide-channels 11 ofplate 10, are mounted the Wheels 16 for the purpose hereinafter to bedescribed. Upon the opposite side of the plate 10 from that shown inFig. 4 is mounted the scroll-plate 17 provided with three spiralchannels 18, adapted to fit the wheels 16, the relative position of saidwheels 16 with respect to the members 12, to which they are secured,being such as to maintain all of said members 12 in relative positionsequidistant from the center or axis of the pulley when said wheels 16are approximately in the initial position, as shown in Fig. 5. It willnow be obvious that the independent rotation of plate member 17 withrespect to plate 10 will cause a spiral movement of said pulleys in thespiral channels 18 and a radial movement of members 12 in the radialgrooves 11 of plate 10. It conse* quently follows that a rotation ofplate 17 with respect to plate 1() in one direction will cause thetravel of members 12 and the overlapping plates 13 outwardly toward thecircumference of plate 10, resulting in an expansion of the pulleyformed by plate members 13, while a relative rotation between saidplates 17 and 10 in an opposite direction will cause said members 12 totravel toward the axis of such rotation, which will result in acontraction of said pulley. This relative movement between plate members10 and 17 is accomplished by the following mechanism: Plate 10 is rigidwith bushing ,20, which is keyed to shaft 21, and consequently rotatestherewith, while the scroll-plate 17 is rotatably mounted on saidbushing-that is, it has a rotation independent thereof. To plate 10 issecured the rim portion 22, Figs. 7, 7 a, and 9, forming the face of oneof the pulleys 1 or 2, both pulleys being substantially alike, and tothis rim or face member 22 is bolted the plate 23, so as to rotate withthe shaft 21. 23 are mounted the gear-Wheel 24, the worm 25, worm-wheel26, and worm 27, and coperating gear 28 28 being mounted on the shaft29, which also carries the spiral gear 30, (see Fig. 10,) whichcoperates with spiral gear 31, secured to the rear side of scroll-plate17. Upon the shaft 21, Figs. 7, 9, and 12, are loosely mounted theoppositely disposed gears 32 and 33, meshing with the gear 24. Gear 32is mounted on and keyed to bushing 34, to which is also keyed the outerring 35 and the lug36. Gear 33 is loosely mounted on the bushing 34 andis provided with the lug 37. A sleeve or collar 38 is slidably mountedon the bushing 39, which surrounds the bushing 34, and is supportedagainst rotation by the trunnions 40 and levers 41 engaging the same.The ring 42 surrounds the ring 35 and is rigidly secured to sleeve 38.The sleeve 38 is provided with the lugs 43, adapted to coperate withlugs 37, and lugs 44, adapted to coperate with lugs 36. The levers 41are secured to the shaft 8, which is controlled, as above stated, byhand-lever 9.

It will be noted that the lever 41 may be moved either forwardly orbackwardly to shift the sleeve 38 to cause the engagement of lugs 43with lugs 37 of gear 33 or to cause the engagement of lugs 44 with lugs36 of gear 32.

Upon the inner side of this plate As above stated, gears 32 and 33 aremounted on shaft 21 and are therefore permitted either to be rotated bygear 24 or to be keyed against such rotation. When the sleeve 38 ismoved to cause the engagement of lugs 37 and 43,the gear 33 is keyedagainst rotation, with a result that when the gear 24 is carried aroundwith the shaft 21 it is caused to rotate in one direction by reason ofits engagement with the fixed gear 33, and when the sleeve 38 is movedin the opposite direction to cause the engagement of lug 36 with lug 44gear 32 is locked against rotation, and in the same manner the gear 24is caused to rotate in the opposite direction. The gear 24 has IOO IIO

operative connection tlxough Worm 25,4

wheel 26, worm 27, wheel 28, and spiral gearwheels 30 and 31 withtheplate 17. It results that the rotation of gear 24, as above described,in either direction causes a corresponding rotation of the scroll-plate17, and, as above stated, the relative turning or rotating of plate 17with respect to plate 10 will cause the movement of the members 12toward or away from the periphery of the wheel to cause the contractionor expansion of the face or periphery of the pulley. It is also obviousthat the parts being properly related the movement of the lever to causethe contraction of one pulley, as above de-u gagement of the propergear-wheel to result in the expansion of the other pulley, and viceversa.

It is a well-known fact in mechanics that a longer belt is required topass around and connect a large and small pulley than is' required fortwo pulleys of the same diameter the mean between the large and thesmall one, the pulleys of course being spaced the same distance betweencenters. It follows from this fact that if one pulley is made tocontract in exactly the same ratio as the other is made to expand, andvice versa, the belt connecting the two would sometimes be loose andsometimes tight. To overcome this difficulty, I have provided the spiralconstruction of gears 30 and 31, which increases the ratio of movementof the scroll-plate to the movement of the shaft driving the pulley.

In view of the fact that there is obviously a limit of the expansive.movement of the pulley parts, it is important to prevent the actuationof the gear 24 in the expanding direction beyond the limit of theexpansive movement of said parts. For this purpose I have rovided thefollowing automatic throw-off. Ilpon the inner side of scroll-plate 17 Ihave secured the stop member 45, while on the plate member 23 I havemounted the rotatable shaft 46. (See Figs. 7, 8, and l0.) This shaft 46is provided at one end with a lever 47, which is adapted to encounterand be actuated by the stop 45, while the other end of the shaft isprovided with a lever 48,which is adapted to encounter and actuate theslide member 49, which engages with the sleeve 3S to cause thedisengagement of lug 44 from lug 36 or lug 37 from lug 43, as the casemay be. The relative positions of stop 45 and lever 47 are such as topermit the desired rotation of scroll member 17 with respect to theshaft 2l and the other parts rotated therewith as shall secure thedesired expansion of the pulley. It is obvious that a correspondingautomatic arrangement on each pulley will serve as an automatic controlin either direction.

What I claim is- 1. In an expansible pulley, the combination of a pairof cooperating independentlyrotatable elements, one having spiral andthe other radial guides,- a train of gearing adapted to operate betweensaid two cooperating elements for causing their relative rotation, saidgearing including means for automatically increasing the ratio betweenthe rates of movement of said elements, and movable rim-sections havingoperative relationship each with a radial and a spiral guide.

2. In an exparsible pulley, the combination of a pair tf cooperatingindependentlyrotatable elements, one having spiral and the other radialguides, a train of gearing adapted to operate between said twocooperating elements for causing their relative rotation, said gearingincluding a pair of spiral gearwheels for increasing the ratio betweenthe rates of movement of said elements, and movable rim-sections havingoperative relationship each with a radial and a spiral guide.

3. In an expansible pulley, the combination of a plurality ofradially-movable faceforming sections, and means for causing themovement of the same, comprising two concentric independently-rotatableelements and a shaft for supporting the same, one element provided withspiral guides, the other with radial guides, train of gearing foractuating said elements relatively, said gear means including a pair ofspiral gear-wheels for increasing the ratio between the rates ofmovement of said elements.

4. In an expansible pulley, the combination of a plurality ofradially-movable faceforming sections, means for causing the movement ofthe same comprising two concentric independently-rotatable elements anda shaft for supporting the same, one element provided with spiralguides, the other with radial guides, a train of gearing for causing therelatively independent rotation of said two elements, said gearingincluding a pair of spiral gears for increasing the ratio between therates of movement of said elements.

5. In an expansible wheel or pulley, the combination of a plurality ofradially-movable face-forming sections and means for causing themovement of the same, comprising two concentric independently-rotatableelements, one provided with spiral guides and the other with radialGuides, a shaft for supporting said rotatable eIements, a train ofgearing for causing the relatively independent rotation of saidelements, and manually-operative means for arbitrarily reversing 'thedirection of said rotation, said gearing including a pair of spiralgears for in creasing the ratio between the rates of movement of thescroll element and the shaft driving the pulley.

6. In a speed-varying mechanism, a pair of expansible pulleys, eachcomprising a plu rality of radially-movable face-forming sections, andmeans for causing the movement of the same, comprising two concentricindependently-rotata ble elements and a shaft for IOO IIO

supporting the same, one element provided with spiral guides, the otherwith radial guides, a train of gearing for actuating said elementsrelatively, said gearing including a pair of spiral gear-wheels forincreasing the ratio between the rates of movement of said elements.

7. In a speed-varying mechanism, a pair of expansible pulleys, eachcomprising a plurality of radially-movable face-forming sections, andmeans for causing the movement of the same, comprising two concentricinde- IZO pendently-rotatable elements and a shaft for elements, andthrow-out mechanism for ausupporting the same, one element provided withspiral guides, the other with radial guides, a train of gearing foractuating said elements relatively, said gearing including a pair ofspiral gear-Wheels for increasing the ratio between the rates ofmovement of said tomaticallyxrendering inoperative the gearactuatingmeans.

JAMES B. LADD. Witnesses:

MAE HOFMANN, LILLIAN M. HUDNUT.

